Schätzung des atmosphärischen Wasserdampfes aus GPS-Messungen und anderen Sondierungsverfahren in der Antarktis

Abstract

The climate is affected by water vapour within the hydrological cycle as it is one of the most variable greenhouse gases. Furthermore atmospheric water vapour transports energy in form of latent heat. All these characteristics make water vapour to one of the most important indicator for a possible global warming. Hence it is possible to detect global climate changes and estimate their impacts with help of long- and short-term developments of atmospheric water vapour. Radiosondes are often used to detect atmospheric parameter beside other measurement systems, but the high logical and finan-cial efforts are common obstacles for using many meteorological measurement systems in extreme climate regions like Antarctica. GPS is an approved method in temperate zones to get meteorological information, but it has had its limits in arid regions in the past. GPS-data of 12 Antarctic GPS-stations were analysed for the years 2000 and 2001 to test the suitability of this method for Antarctica. The fact that many GPS-stations are in-stalled on the Antarctic ice-shield was also taken into account. The pre-cipitable water vapour values out of GPS-measurements were compared with radiosonde launches at six stations to make an examination of quality. They were correlated to radiosonde measurements between 0.8 and 0.95 except the South Pole with 0.21 and high accuracies of GPS-ZTD-values in mm-range were also verified.